(a) Field of the Invention
The present invention relates to a multi-purpose support structure, and more particularly, to one that expands for multiple applications, readily extendable both in width and length by combination with minimum derived members, and foldable for saving storage space.
(b) Description of the Prior Art
Whereas appliances for daily use are compact and multi-purpose designed nowadays to facilitate storage or be readily for conversion to another type of combined use, multi-purpose oriented design has become one of the important means for market expansion to offer agile and diversified optional functions for soliciting the buying urge among the consumers. Accordingly, KD cabinets and racks are available in the market. Usually, those cabinets and racks are essentially comprised of multiples of supports erected into a structure of one or more than one level and then fastened or placement of soft fabrics for accommodation of objects, and dismantled when not used. Said KD structure allows reduced packaging for transportation and sales. However, most of those supports are related to tubes for alternative and cross insertion. Those tubes can be disconnected for storage, but they must be fastened into bundles or bagged. Besides, it consumes too much time for erection.
The primary purpose of the present invention is to provide a multi-purpose support structure that is expandable for multiple applications, extendable both in width and length when combined with the minimum derived members, and foldable for storage without knocking down the members. To achieve the purpose, at least four retractable erection tubes with each two abutted erection tubes pivoted each at its both ends to two connecting rods in cross to form a rectangular frame. Wherein, said two cross connecting rods are alternatively pivoted at their centers. Each of said erection tube is composed of an inner tube inserted into an outer tube to become retractable. A pivoting holder is each provided at the upper and the lower top of each rod. An insertion hole is formed at the center of the pivoting holder and two side slots are formed to the pivoting holder to allow the insertion of the upper and the lower ends of two abutted cross connecting rods. Accordingly, while said connecting rods are expanded, the erection tubes stretch outward and reduce longitudinally in dimension to form the rectangular frame. A top surface defined by those upper pivoting holders of the rectangular frame is incorporated with fixing elements to hold a pavement of canvas or similar material, or a container being inserted into the inner space defined by the rectangular frame to become a unit functioning as a support structure for a rack or a container.
Another purpose of the present invention is to provide a multi-purpose support structure that is expandable both in width and length without limitation. To achieve the purpose, a T-shaped pivoting holder containing a three-way trough connected to both ends of each erection tube for the trough to be located between two erection tubes from the outer frame and connected to sets of cross connecting rods for expansion. The central trough of the T-shaped pivoting holder can be further pivoted to longitudinally provided cross connecting rods for segregation and reinforcement purposes in enlarging the volume available by stretching up the support structure. Accordingly, a longer support structure is provided with top surface placed with multiple pieces of canvas to form a camp bed if required.